Aseven digit telephone number is of the form abc-defg. in one particular state, the
digit ‘a’ can be any digit except 8 and 9. the digits b and c can be any digit from 1 - 8.
the digits d, e, f, and g can be any digit 0 – 9 except they can’t all be the same (e. g.
, , , …. how many seven digit phone numbers are possible with
these restrictions?
5,120,000
5,114,880
4,608,000
10,000,000

solution:

the given function is ,

      =

the three roots of this quadratic function is , 0 ,8 and 10.all the roots are real and rational.

if a quadratic equation is of the form ,

sum of the roots = a + b +c= 0+8+10=18=  

product of roots taken two at a time = a b + b c+ c a = 0+80+0=80 =  

product of roots = a b c = 0=  

there are 11 doors in a hall starting from 0 to 11.the entry in the hall is permitted through gate number 0 and exit is allowed through only gate number 8 and 10.so, three roots(0,8,10) of quadratic function is given by entry and exit route of this hall.

answer: (-6,3)

step-by-step explanation:

-3 degrees

step-by-step explanation: